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Related papers: On mini-halo encounters with stars

200 papers

Based on a set of cosmological N-body simulations we analyze properties of the dark matter haloes (DM) in a galaxy mass range ($10^{11} - 10^{13} h^{-1}M_{\odot}$) in modified $\lcdm$ cosmology with additional dynamically screened scalar…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-31 Wojciech A. Hellwing

The distribution of dark matter in the Milky Way (MW) is expected to exhibit a large-scale dynamical response to the recent infall of the LMC. This event produces a dynamical friction wake and shifts the MW's halo density center. The…

In the context of increasing appreciation for the coupling between the Galactic bar and the halo, we introduce a new framework using stars trapped in resonance with the bar to probe the Galactic dark matter subhalo population. Since…

Astrophysics of Galaxies · Physics 2026-03-06 Elliot Y. Davies , Adam M. Dillamore , Vasily Belokurov , Lina Necib

We study the distribution of cold dark matter (CDM) in cosmological simulations from the FIRE (Feedback In Realistic Environments) project, for $M_{\ast}\sim10^{4-11}\,M_{\odot}$ galaxies in $M_{\rm h}\sim10^{9-12}\,M_{\odot}$ halos. FIRE…

Astrophysics of Galaxies · Physics 2015-10-28 T. K. Chan , D. Kereš , J. Oñorbe , P. F. Hopkins , A. L. Muratov , C. -A. Faucher-Giguère , E. Quataert

We study the internal response of a galaxy to an unbound encounter and present a survey of orbital parameters covering typical encounters in different galactic environments. Overall, we conclude that relatively weak encounters by low-mass…

Astrophysics · Physics 2009-10-31 E. Vesperini , Martin D. Weinberg

Self-interacting dark matter provides a promising alternative for the cold dark matter paradigm to solve potential small-scale galaxy formation problems. Nearly all self-interacting dark matter simulations so far have considered only…

Astrophysics of Galaxies · Physics 2019-03-19 Mark Vogelsberger , Jesús Zavala , Katelin Schutz , Tracy R. Slatyer

Galaxy sizes correlate closely with the sizes of their parent dark matter haloes, suggesting a link between halo formation and galaxy growth. However, the precise nature of this relation and its scatter remains to be understood fully,…

We study the impact of numerical parameters on the properties of cold dark matter haloes formed in collisionless cosmological simulations. We quantify convergence in the median spherically-averaged circular velocity profiles for haloes of…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 Aaron D. Ludlow , Joop Schaye , Richard Bower

In a serie of three papers, the dynamical interplay between environments and dark matter haloes is investigated, while focussing on the dynamical flows through their virial sphere. Our method relies on both cosmological simulations, to…

Astrophysics · Physics 2008-11-26 Dominique Aubert , Christophe Pichon

We present a model for gas heating, driven by dynamical friction from orbiting subhalos within dark matter halos. Using data from the TNG50 simulation, we derive the subhalo mass function and calculate the dynamical friction heating rate…

Astrophysics of Galaxies · Physics 2026-03-23 Zhenyu Wu , Sadegh Khochfar , Muhammad A. Latif , Ben Morton , Britton Smith

In the second paper of this series, we present results from cosmological simulations on the demographics of flyby interactions to gauge their potential impact on galaxy evolution. In a previous paper, we demonstrated that flybys -- an…

Astrophysics of Galaxies · Physics 2015-06-01 Manodeep Sinha , Kelly Holley-Bockelmann

High-resolution N-body simulations are used to examine the power spectrum dependence of the concentration of galaxy-sized dark matter halos. It is found that dark halo concentrations depend on the amplitude of mass fluctuations as well as…

Astrophysics · Physics 2009-07-09 V. R. Eke , J. F. Navarro , M. Steinmetz

Dark matter (DM) self-interactions have been proposed to solve problems on small length scales within the standard cold DM cosmology. Here, we investigate the effects of DM self-interactions in merging systems of galaxies and galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-19 Moritz S. Fischer , Marcus Brüggen , Kai Schmidt-Hoberg , Klaus Dolag , Antonio Ragagnin , Andrew Robertson

We compare the dark matter halos' structural parameters derived for four Milky Way dwarf spheroidal galaxies to those of subhalos found in cosmological $N$-body simulations. We confirm that estimates of the mass at a single fixed radius are…

Astrophysics of Galaxies · Physics 2015-12-02 Maarten A. Breddels , Carlos Vera-Ciro , Amina Helmi

The distribution of orbital energies imparted into stellar debris following the close encounter of a star with a supermassive black hole is the principal factor in determining the rate of return of debris to the black hole, and thus in…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Sarah Norman , Chris Nixon , Eric R. Coughlin

We present a simple technique to estimate mass-to-light (M/L) ratios of stellar populations based on two broadband photometry measurements, i.e. a color-M/L relation. We apply the color-M/L relation to galaxy rotation curves, using a large…

Astrophysics · Physics 2007-05-23 Roelof S. de Jong , Susan Kassin , Eric F. Bell , Stephane Courteau

High-resolution N-body simulations of dark matter halos indicate that the Milky Way contains numerous subhalos. When a dark matter subhalo passes in front of a star, the light from that star will be deflected by gravitational lensing,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Adrienne L. Erickcek , Nicholas M. Law

Close encounters between stars and black holes can trigger micro-tidal disruption events (micro-TDEs) in dense young star clusters (YSCs). Using direct N-body simulations with PETAR, we found that most micro-TDEs arise from few-body…

High Energy Astrophysical Phenomena · Physics 2025-09-17 Sara Rastello , Giuliano Iorio , Mark Gieles , Long Wang

We point out that the usual self-similarity in cold dark matter models is broken by encounters with individual normal galactic stars on sub-pc scale. Tidal heating and stripping must have redefined the density and velocity structures of the…

Astrophysics · Physics 2010-11-11 HongSheng Zhao , Dan Hooper , Garry W. Angus , James E. Taylor , Joseph Silk

We develop a linear perturbative formalism to compute the response of an inhomogeneous stellar disk embedded in a non-responsive dark matter halo to perturbations like bars, spiral arms and satellite galaxy encounters. Without self-gravity…

Astrophysics of Galaxies · Physics 2023-07-26 Uddipan Banik , Frank C. van den Bosch , Martin D. Weinberg